Basic Allergy Diagnosis and Treatment

Many of us enjoy the changing seasons, but for some these changes bring on a host of allergens that cause watery, dirty, red, messy, irritated eyes. When a patient presents with these symptoms, allergies should be on your mind in the differential diagnosis, but dryness and ocular surface disease should also be considered as possible culprits.

UNDERSTANDING THE ALLERGIC RESPONSE PROCESS

Typically, allergic response is a two-step process. Step one occurs when an individual is first exposed to an allergen (antigen) and immunoglobulin E (IgE)-mediated antibodies join with associated mast cells, become activated, and take up residence in areas of the body most susceptible to additional exposure. At this point, the body is sensitized to the antigen but is not yet symptomatic. Step two happens with additional exposure. The now IgE-specific mast cells release histamine and prostaglandins, causing swelling, itching, pain, smooth muscle contraction, and vasodilation. The greater the exposure to the antigen, the more the mast cells are stimulated and the greater the allergic response.¹

DIAGNOSIS

Patients may self-diagnose and decide to use over-the-counter allergy drops and vasoconstrictors, which can aggravate symptoms. Although many of us think of itching as the hallmark symptom of allergies, patients may also complain of redness, watery eyes, swelling of the eyelids, and mattery eyes.

Thus, a comprehensive history is a must to try to determine whether the patient has dry eye disease, an infection, or ocular allergies. It’s essential to know when the patient’s symptoms first occurred, how long he or she has been symptomatic, whether the symptoms are worsening, when and where the symptoms typically occur, and whether there are other modifying factors (eg, worse at work or better at home).

In patients with allergy, slit-lamp examination should reveal papillae on the inner palpebral conjunctiva of both upper and lower lids. Inflammation can be moderate or severe enough to cause the puncta to swell shut. The resulting lack of tear-film circulation and constant exposure of the ocular surface to antigens only exacerbates the allergic condition further. Surgical solutions (eg, punctoplasty or insertion of a polyvinylpyrrolidone punctal plug) may be necessary to open the puncta.

In-office point-of-care allergy testing can help clinicians figure out the cause of a patient’s symptoms. Doctor’s Allergy Formula (Bausch + Lomb) is an FDA-approved in-office allergy scratch test performed on a patient’s arms in the clinic setting. See Key Points for Allergy Testing above for a list of considerations to take into account before scheduling patients for testing. The test, which is usually covered by most insurance companies, includes a panel of 60 allergens specific to your part of the country. It takes about 3 minutes to administer, and results are ready within 15 minutes.

TREATMENT TALK

Avoidance of the offending allergen or allergens is the only guaranteed way to improve allergy symptoms, but that’s not always a realistic solution. Common treatment tactics (Table) include the use of systemic and topical antihistamines and combination antihistamine/mast-cell stabilizers. Topical steroids and nonsteroidal antiinflammatory drugs may also be used. If these options don’t deliver satisfactory outcomes, it may be necessary to consider in-office allergy testing to determine the root cause of the patient’s complaints.

If complete avoidance of the causative agents identified is not possible, in the past, allergists would administer weekly injections of immunotherapy shots, but now patients can opt for daily sublingual immunotherapy to desensitize their immune systems over a period of several weeks to months.

I believe that patients are more understanding and compliant with treatment recommendations when they know that there truly is a causative factor for their symptoms. Note: Check with your local state laws for clarity regarding optometry’s ability to perform these tests.

IT PAYS TO BE SURE

Allergic eye disease can be difficult to diagnose. Ruling out dry eye disease and infectious causes is an important step to take before initiating treatment. Knowing the root cause of a patient’s symptoms will prove helpful in finding appropriate solutions. Furthermore, figuring out the causative factor and creating a customized plan will impress your patients, improve their outcomes, and set your practice apart from others in the area.